Mast cells secrete

• hippurin

• myoglobin

• histamine

• histamine

C.

histamine

Histamine is a protein, acting as a vasodilator (widening of blood vessels) in inflammatory and allergic reactions and also increases the permeability of small vessels. It is secreted from the mast cells which widely occur in the aerolar connective tissue.
Two other active substances secreted by mast cells are Heparin, a proteoglycan, which prevents coagulation of blood vessels and serotonin, a protein, which acts as vasoconstrictor to stop bleeding and to increase blood pressure.

D.

thrombocytes

AIDS (Acquired Immuno Deficiency Syndrome) is caused by HIV (Human immuno deficiency virus). T4 lymphocytes are the principal target cells of HIV.

D.

Alzheimer's disease

Rheumatoid arthritis is an autoimmune disorder in which antibodies are produced against the synovial membrane and cartilage.

Vitiligo causes white patches on skin also characterised as the autoimmune disorder.

Psoriasis is a skin disease that causes itchy or sore patches of thick red skin and is also autoimmune.

Alzheimer's disease is a neurodegenerative disorder due to deficiency of neurotransmitter acetylcholine.

B.

Cell-mediated immune response

Non-acceptance or rejection of graft or transplanted tissues/organs is due to cell mediated immune response

A.

Elephantiasis

Lymphatic filariasis, also known as elephantiasis, is a human disease caused by parasitic worms known as filarial worms. It is caused by roundworm, Wuchereria bancrofti and it is transmitted by culex mosquito.